module anim

import gg
import sim
import sim.args as simargs

const bg_color = gg.white

struct Pixel {
    x     f32
    y     f32
    color gg.Color
}

pub struct App {
pub:
    args         simargs.ParallelArgs
    request_chan chan &sim.SimRequest
    result_chan  chan &sim.SimResult
pub mut:
    gg     &gg.Context = unsafe { nil }
    iidx   int
    pixels []u32
}

pub fn new_app(args simargs.ParallelArgs) &App {
    total_pixels := args.grid.height * args.grid.width

    mut app := &App{
        args:         args
        pixels:       []u32{len: total_pixels}
        request_chan: chan &sim.SimRequest{cap: args.grid.width}
    }
    app.gg = gg.new_context(
        width:         args.grid.width
        height:        args.grid.height
        create_window: true
        window_title:  'V Pendulum Simulation'
        user_data:     app
        bg_color:      bg_color
        frame_fn:      frame
        init_fn:       init
    )
    return app
}

fn init(mut app App) {
    app.iidx = app.gg.new_streaming_image(app.args.grid.width, app.args.grid.height, 4,
        pixel_format: .rgba8
    )
    spawn pixels_worker(mut app)
}

fn frame(mut app App) {
    app.gg.begin()
    app.draw()
    app.gg.end()
}

fn (mut app App) draw() {
    mut istream_image := app.gg.get_cached_image_by_idx(app.iidx)
    istream_image.update_pixel_data(unsafe { &u8(&app.pixels[0]) })
    app.gg.draw_image(0, 0, app.args.grid.width, app.args.grid.height, istream_image)
}